Generator doesn't generate nullable parameters always

[vasov97]

Description of the bug

Generator doesn't generate nullable parameters always - some classes have some parameters nullable when generated (ex: String? name), but not all classes and that is becoming big issue for an app. I have to change them manually every time when i generate it again (and no, i can't put it in openiapi-ignore file, because that classes will change on backend).

Steps to reproduce

Just run generator as usually

Expected behavior

To have all parameters of the class generated as nullable types

Logs

No response

Screenshots

No response

Platform

macOS

Library version

4.11.0

Flutter version

3.16.9

Flutter channel

stable

Additional context

No response